cosh(arctan(x)*arctan(x))=1+12/4!*x^4-480/6!*x^6+31248/8!*x^8...

A012465

cosh(arctan(x)*arctan(x))=1+12/4!*x^4-480/6!*x^6+31248/8!*x^8...

Terms

    a(0) =1a(1) =0a(2) =12a(3) =-480a(4) =31248a(5) =-3160320a(6) =462297792a(7) =-92467554816

External references